Packaging Design of 15 kV SiC Power Devices With High-Voltage Encapsulation

Silicon carbide (SiC) is capable of improving the blocking voltage of power devices. It is essential to package SiC power devices for high-voltage applications. This article proposes a high-voltage packaging method for >15-kV SiC power devices by designing an optimized stacked direct bond copper (DBC) substrate with a copper ring and a field-dependent conductivity (FDC) encapsulation using SiC as the filler. The proposed FDC encapsulation is proven as a promising encapsulation as commercial silicone. The partial discharge initial voltage (PDIV) of the demonstrated module using the proposed method can be improved to at least 18.31 kV, which is increased by 163.77% compared with the typical 34-mm insulated gate bipolar transistor (IGBT) modules. The maximum voltage rating of the demonstrated module could be enhanced to at least 15 kV with a sufficient protection margin, i.e., 20%. It gives guidance to the packaging of >15-kV SiC power devices.